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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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bitcoin / bitcoinstable

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bitcoin / src / util / subprocess.h

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1251    }
1252    if (err.wr_ch_ != -1) popen_->stream_.err_write_ = err.wr_ch_;
1253    if (err.rd_ch_ != -1) popen_->stream_.err_read_ = err.rd_ch_;
1254  }
1255
1256
1257#ifndef WIN32
1258  inline void Child::execute_child() {
1259    int sys_ret = -1;
1260    auto& stream = parent_->stream_;
1261
1262    try {
1263      if (stream.write_to_parent_ == 0)
1264        stream.write_to_parent_ = dup(stream.write_to_parent_);
1265
1266      if (stream.err_write_ == 0 || stream.err_write_ == 1)
1267        stream.err_write_ = dup(stream.err_write_);
1268
1269      // Make the child owned descriptors as the
1270      // stdin, stdout and stderr for the child process
1271      auto _dup2_ = [](int fd, int to_fd) {
1272        if (fd == to_fd) {
1273          // dup2 syscall does not reset the
1274          // CLOEXEC flag if the descriptors
1275          // provided to it are same.
1276          // But, we need to reset the CLOEXEC
1277          // flag as the provided descriptors
1278          // are now going to be the standard
1279          // input, output and error
1280          util::set_clo_on_exec(fd, false);
1281        } else if(fd != -1) {
1282          int res = dup2(fd, to_fd);
1283          if (res == -1) throw OSError("dup2 failed", errno);
1284        }
1285      };
1286
1287      // Create the standard streams
1288      _dup2_(stream.read_from_parent_, 0); // Input stream
1289      _dup2_(stream.write_to_parent_,  1); // Output stream
1290      _dup2_(stream.err_write_,        2); // Error stream
1291
1292      // Close the duped descriptors
1293      if (stream.read_from_parent_ != -1 && stream.read_from_parent_ > 2)
1294        subprocess_close(stream.read_from_parent_);
1295
1296      if (stream.write_to_parent_ != -1 && stream.write_to_parent_ > 2)
1297        subprocess_close(stream.write_to_parent_);
1298
1299      if (stream.err_write_ != -1 && stream.err_write_ > 2)
1300        subprocess_close(stream.err_write_);
1301
1302      // Replace the current image with the executable
1303      sys_ret = execvp(parent_->exe_name_.c_str(), parent_->cargv_.data());
1304
1305      if (sys_ret == -1) throw OSError("execve failed", errno);
1306
1307    } catch (const OSError& exp) {
1308      // Just write the exception message
1309      // TODO: Give back stack trace ?
1310      std::string err_msg(exp.what());
1311      //ATTN: Can we do something on error here ?
1312      util::write_n(err_wr_pipe_, err_msg.c_str(), err_msg.length());
1313    }
1314
1315    // Calling application would not get this
1316    // exit failure
1317    _exit (EXIT_FAILURE);
1318  }
1319#endif
1320
1321
1322  inline void Streams::setup_comm_channels()
1323  {
1324#ifdef WIN32
1325    util::configure_pipe(&this->g_hChildStd_IN_Rd, &this->g_hChildStd_IN_Wr, &this->g_hChildStd_IN_Wr);
1326    this->input(util::file_from_handle(this->g_hChildStd_IN_Wr, "w"));
1327    this->write_to_child_ = subprocess_fileno(this->input());
1328
1329    util::configure_pipe(&this->g_hChildStd_OUT_Rd, &this->g_hChildStd_OUT_Wr, &this->g_hChildStd_OUT_Rd);
1330    this->output(util::file_from_handle(this->g_hChildStd_OUT_Rd, "r"));
1331    this->read_from_child_ = subprocess_fileno(this->output());
1332
1333    util::configure_pipe(&this->g_hChildStd_ERR_Rd, &this->g_hChildStd_ERR_Wr, &this->g_hChildStd_ERR_Rd);
1334    this->error(util::file_from_handle(this->g_hChildStd_ERR_Rd, "r"));
1335    this->err_read_ = subprocess_fileno(this->error());
1336#else
1337
1338    if (write_to_child_ != -1)  input(fdopen(write_to_child_, "wb"));
1339    if (read_from_child_ != -1) output(fdopen(read_from_child_, "rb"));
1340    if (err_read_ != -1)        error(fdopen(err_read_, "rb"));
1341
1342    auto handles = {input(), output(), error()};
1343
1344    for (auto& h : handles) {
1345      if (h == nullptr) continue;
1346      setvbuf(h, nullptr, _IONBF, BUFSIZ);
1347    }
1348  #endif
1349  }
1350
1351  inline int Communication::send(const char* msg, size_t length)
1352  {
1353    if (stream_->input() == nullptr) return -1;
1354    return std::fwrite(msg, sizeof(char), length, stream_->input());
1355  }
1356
1357  inline int Communication::send(const std::vector<char>& msg)
1358  {
1359    return send(msg.data(), msg.size());
1360  }
1361
1362  inline std::pair<OutBuffer, ErrBuffer>
1363  Communication::communicate(const char* msg, size_t length)
1364  {
1365    // Optimization from subprocess.py
1366    // If we are using one pipe, or no pipe
1367    // at all, using select() or threads is unnecessary.
1368    auto hndls = {stream_->input(), stream_->output(), stream_->error()};
1369    int count = std::count(std::begin(hndls), std::end(hndls), nullptr);
1370    const int len_conv = length;
1371
1372    if (count >= 2) {
1373      OutBuffer obuf;
1374      ErrBuffer ebuf;
1375      if (stream_->input()) {
1376        if (msg) {
1377          int wbytes = std::fwrite(msg, sizeof(char), length, stream_->input());
1378          if (wbytes < len_conv) {
1379            if (errno != EPIPE && errno != EINVAL) {
1380              throw OSError("fwrite error", errno);
1381            }
1382          }
1383        }
1384        // Close the input stream
1385        stream_->input_.reset();
1386      } else if (stream_->output()) {
1387        // Read till EOF
1388        // ATTN: This could be blocking, if the process
1389        // at the other end screws up, we get screwed as well
1390        obuf.add_cap(out_buf_cap_);
1391
1392        int rbytes = util::read_all(
1393                            stream_->output(),
1394                            obuf.buf);
1395
1396        if (rbytes == -1) {
1397          throw OSError("read to obuf failed", errno);
1398        }
1399
1400        obuf.length = rbytes;
1401        // Close the output stream
1402        stream_->output_.reset();
1403
1404      } else if (stream_->error()) {
1405        // Same screwness applies here as well
1406        ebuf.add_cap(err_buf_cap_);
1407
1408        int rbytes = util::read_atmost_n(
1409                                  stream_->error(),
1410                                  ebuf.buf.data(),
1411                                  ebuf.buf.size());
1412
1413        if (rbytes == -1) {
1414          throw OSError("read to ebuf failed", errno);
1415        }
1416
1417        ebuf.length = rbytes;
1418        // Close the error stream
1419        stream_->error_.reset();
1420      }
1421      return std::make_pair(std::move(obuf), std::move(ebuf));
1422    }
1423
1424    return communicate_threaded(msg, length);
1425  }
1426
1427
1428  inline std::pair<OutBuffer, ErrBuffer>
1429  Communication::communicate_threaded(const char* msg, size_t length)
1430  {
1431    OutBuffer obuf;
1432    ErrBuffer ebuf;
1433    std::future<int> out_fut, err_fut;
1434    const int length_conv = length;
1435
1436    if (stream_->output()) {
1437      obuf.add_cap(out_buf_cap_);
1438
1439      out_fut = std::async(std::launch::async,
1440                          [&obuf, this] {
1441                            return util::read_all(this->stream_->output(), obuf.buf);
1442                          });
1443    }
1444    if (stream_->error()) {
1445      ebuf.add_cap(err_buf_cap_);
1446
1447      err_fut = std::async(std::launch::async,
1448                          [&ebuf, this] {
1449                            return util::read_all(this->stream_->error(), ebuf.buf);
1450                          });
1451    }
1452    if (stream_->input()) {
1453      if (msg) {
1454        int wbytes = std::fwrite(msg, sizeof(char), length, stream_->input());
1455        if (wbytes < length_conv) {
1456          if (errno != EPIPE && errno != EINVAL) {
1457            throw OSError("fwrite error", errno);
1458          }
1459        }
1460      }
1461      stream_->input_.reset();
1462    }
1463
1464    if (out_fut.valid()) {
1465      int res = out_fut.get();
1466      if (res != -1) obuf.length = res;
1467      else obuf.length = 0;
1468    }
1469    if (err_fut.valid()) {
1470      int res = err_fut.get();
1471      if (res != -1) ebuf.length = res;
1472      else ebuf.length = 0;
1473    }
1474
1475    return std::make_pair(std::move(obuf), std::move(ebuf));
1476  }
1477
1478} // end namespace detail
1479
1480}
1481
1482#endif // BITCOIN_UTIL_SUBPROCESS_H
1483

A READING COMPANION

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This file is included in the stable source snapshot. A file-specific guide has not been published yet.

440 guided files · 2,580 pending. Guides cover key sections, not every line.

cmake/bitcoin-build-config.h.in src/consensus/amount.h src/consensus/consensus.h src/primitives/block.h src/primitives/transaction.h src/crypto/sha256.h src/util/moneystr.h src/clientversion.h src/uint256.h src/script/script.h src/policy/policy.h CMakeLists.txt README.md COPYING src/consensus/tx_check.cpp src/consensus/tx_verify.cpp src/consensus/merkle.cpp src/pow.cpp src/validation.cpp src/script/interpreter.cpp src/script/solver.cpp src/script/sign.cpp src/key_io.cpp src/net.cpp src/net_processing.cpp src/netaddress.cpp src/protocol.h src/wallet/wallet.cpp src/wallet/spend.cpp

← Previous 250 linesCode page 6

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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